Related Applications
This application is related to co-pending application Ser. Nos. 06/861,482 and 06/861,483 both filed on May 9, 1986.
The invention refers to an electrically actuatable fuel-injection valve for internal combustion engines.
Such known fuel-injection valves are actuated by a solenoid whose magnet winding is arranged within a central bore in a valve housing (German Fed. Republic Pat. No. 23 49 584). A soft-iron core is inserted into the magnet winding, the core being developed outside the valve housing as a connection nipple for the feeding of the fuel. An armature is so arranged opposite the end of the soft-iron core that an air gas is formed between these two parts. A valve needle which is guided for longitudinal displacement in a tapered end of the valve housing is arranged on the armature. The valve needle is so developed, in particular with flat surfaces ground on its body, that fuel can flow into an annular space in front of a valve seat of the valve needle. When the solenoid is energized, the armature attracts the valve needle which thus opens the valve. Fuel under pressure is injected into the internal combustion engine through a metering slot which is then opened. The manufacture of such fuel-injection valves which have a longitudinally displaceable valve needle is expensive since the fuel-injection valve consists of many parts which must be manufactured, in part, with high precision and then mounted.
Furthermore, the longitudinally displaceable valve needles and their support are subject to wear, as a result of which the amount of feed can be modified. The actuating of this electromagnetic fuel-injection valve requires substantial electric power, for which suitably dimensioned components must be provided.